Method of forming ornamented surfaces



Jan. 17, 1956 D, w. Ko ETAL 2,731,333

METHOD OF FORMING ORNAMENTED SURFACES Filed May 13, 1954 2 Sheets-Sheet l FIG. l.

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"III'III' F'G- |7 WILLIAM MAUCHENBACH ATTORNEY 2 Sheets-Sheet 2 D. W. KO ET AL METHOD 0F FORMING ORNAMENTED SURFACES 4e f D/y 52 Y if w/@w M \ruyum 46- F I G. 2 l.

Jan. 17, 1956 Filed May 15, 1954 INV ENTORS DAVID W. KO

ATTORNEY United States Patent() METHOD F FGRMING CRNAMENTED SURFACES David W. Ko, Wesley Ko and William M. Anchenbach, Philadelphia, Pa., assignors to Komak, lne., Philadel`phia,Pa.,` a corporation of Pennsylvania Application May 13, 1954, Serial No. 429,574 l 3Cl'ams. (Cl. 41-43) The present invention relates to the treatment of surfaces of metal-nonmetal laminates and it relates more particularly to the formationof decorative or ornamental effects` and. of insignia,` indicia, and the like upon metal- 4on-nonmetal laminates, by an etching or intaglio process whichA provides suitable contrasts by making the underlying nonmetal` material visible in contrast to the main metal outer surface.

` An object of the present invention is to provide a new and useful method of forming ornamented or otherwise markedsurfaces. Another object ofthe present invention is toprovide a novel method of ornamenting or otherwise marking the surfaceV of a metal-on-nonmetal laminate, as well as to provide new anduseful articles of manufacture formed thereby. A `further object ofthe present invention is to provide a relatively simple and inexpensive process for forming etched or intaglio decorated or otherwise marked surfaces upon metal-on-plastic laminates, and also` to provide new and useful articles of manufacture produced thereby. p

Other objects and advantages ofl the present invention areapparent in the following detailed description, appended claims and accompanying drawings.

It has heretofore been suggested to deposit relative thin outer sheets or lms ofrnetallic material upon nonmetallicl bases to form laminates. It has also been suggested to print upon. the metal surface with an acid-resistant ink or the likeand thereafter to etch away the uncoated metal so as to leave metal only in the areas ofthe print. The latter process has been usedespecially in the formation of" so-called printed electrical circuits, in which strips of conducting materialA are thus formed on a base of" synthetic resin having appropriate dielectric properties andreplace the conventional electricalwires of the circuit.

According to the' present invention, it has been found that strikingly attractive and beautiful effects, ornamental as well` as utilitarian, can be achieved easily and inexpensivelyby a novel method of forming decorative or other appropriate etched or intaglio markings uponthe surface of ametal-on-nonmetal laminate, and more particularly a laminate comprising one or more superimposed coatings of differentLcolored metal, upon a contrastingly coloredbase of synthetic resin or the lik l For `the purpose of illustrating the invention, there are shown, in the accompanying drawings, forms thereof `which are presently preferred; it being understood, however,`that` the invention is not limited to the-precise arrangements and instrumentalities illustrated.

Referring to the accompanying drawings in which like reference` characters indicate like parts throughout:

Figure, 1 isa front elevational viewof an ornamental plaque forming oneembodiment ofthe present invention; the design having been formed by partial Ietching of a light-coloredmetal coating onta dark-colored: synthetic resin base.

Figure 2 isgafragmen-tary cross-sectional view of the.

original non-etched metal-on-resin plate, from which the ICC plaque of Fig. 1 is formed by means of the successive steps illustrated in Figs. 3-5.

Figure 3 is a fragmentary cross-sectional view like that of Fig. 2, showing the appearance of the plate after an acid resist has been imprinted thereon in an appropriate design.

Figure 4 is a view like those of Figs. 2 and 3 but showing the appearance of the plate after the unprotected portions of the metal coating have been etched away, to expose the underlying resin base.

Figure 5 is a View like those of Figs. 2-4 but showing the appearance of the etched plate, after removal of the resist.

Figure 6 is a fragmentary cross-sectional View, like that of Fig. 2, but showing twosuperimposed metal coatings, namely an outermost basel metal coating and an undercoating of precious metal, upon a contrastingly colored synthetic resin base.

Figure 7 is a view like that of Fig. 6 but showing a resist coating imprinted thereon in an appropriate design.

Figure 8 is a view showing the plate of Figs. 6 and 7 after the exposed areas of the outermost coating have been etched away by treatment with an etching agent which does not attack the precious metal.

Figure 9 is a view showing the appearance of the plate of Fig. 8 after removal of the resist coating therefrom.

Figure i0 shows the appearance of the plate of Fig. 9 after the resist has been imprinted thereon in a new design.

Figure ll' shows the appearance of the plate after the uncoated areas have been etched away by exposure to an etching agent capable of attacking both the base metal and precious metal layers.

Figure l2 is a view showing the final appearance of the plate of Figs. 6-11 and indicating how both the resin base and the precious metal undercoating are` visible, at different points, in contrast to the base metal. outer coat, to form the final composite three-color design.

Figure 13 is a View like that of Fig. 6 showing two superimposed metal coatings, namely an outermost copper coating and an undercoating of aluminum,` upon a synthetic resin base.

Figure 14 isa view like that ofv Fig. 13 but showing a resist coating imprinted thereon in an appropriate design.

Figure l5 is a view showing the plate of Figs. 13 and 14 after the uncoated areas have been etched away by treatment with an etching agent capable of attacking both the copper layer and' the aluminum layer.

Figure 16 is aview showing the appearance of the plate of Fig. 151 after removal of the resist coatingtherefrom.

Figure 17 shows the appearance of the plate of Fig.` 16' after` the resist has been imprinted thereon in a new design.

Fig. 18 shows the appearance of the plate of Fig. 1:7 after the uncoated areas have been. etched away by treatment with` an etching agent capable of attacking only the outer copper layer.

Figure 19 is a view showing the iinal appearance of the plate of; Figs. l3-18`after removalof the resist, and. indicating how both the resin base and the aluminum undercoating are Visible, at different points, in contrast to the copper outer coating.

Figure `20 isa topplan view of atable top with a pair of` ornamental plaques, similar to that of Fig. l, set in to form a moref or less integral part thereof.

Figure 2l is` a front elevational View of the front panel of a portable radio showing the name, tuning-dial insignia, and switch insignia formed, in contrastinglyv coloredl a printed electrical circuit formed on the inner side of the panel of Fig. 21.

Figure, 23 is a fragmentary cross-sectional View showing the appearance of the panel of Figs. 21 and 22 at a preliminary stage of formation; that is, with a coating of contrastingly colored metal applied to the outer surface and a coating of electrically conducting metal applied to the inner surface of the synthetic resin panel, in which shaft holes and the like have not yet been formed.

Figure 24 is a view like that of Fig. 23 but showing resist imprinted upon the respective metal coatings in appropriate designs.

Figure 25 shows the appearance of the panel of Figs. 23 and 24 after the unprotected areas of the respective metal coatings have been etched away, exposing the resin base.

Figure 26 is a view showing the appearance of the panel of Figs. 23-25 after removal of the resist.

Figure 27 is a view showing the nal appearance of the panel of Figs. 23-26 after formation Vof the shaft hole 44 therein.

In Fig. l there is shown an ornamental plaque having a two-tone ornamental design formed by partial removal of a light-colored metal coating on a dark-colored synthetic resin base.

The base 30 may be formed of any suitable synthetic resin, either opaque orV light-transmitting. WhereV an opaque synthetic resin is employed, it is preferably of a color lwhich contrasts with the color of the metal coating. Thus, where the metal is light in color, the synthetic resin is preferably dark in color. On the other hand, where a relatively dark colored metal is employed, the synthetic resin is preferably lighter in color than the metal.

A wide range of synthetic resins can be used for this purpose, including, for example, Bakelite or other phenol-formaldehyde resin, nylon, silicone resin, Teflon, Epoglass, Plexiglass, breglass resin, and many others.

Similarly, the metal coating may be of copper, brass, aluminum, nickel, silver, gold, and various other precious and non-precious metals, alloys and the like.

The metal coating may be applied to the resin plate in any conventional manner, known to those skilled in the art, as for example by electro-plating, spraying, dipping, laminating (under the action of heat and pressure), etc.

Where two or more superimposed coatings are employed, the individual coatings may be applied in different ways. Thus, for example, one coating may be applied by laminating and the second by electro-plating, and vice versa.

For purposes of illustration, in the following example, the base 30 is described as being of dark-colored phenolformaldehyde synthetic resin and the metal surface 32 is described as being of copper.

Starting with the copper-on-resin laminate, as shown in Fig. 2, the rst step in the formation of the ornamental plaque of Fig. 1 is the imprinting upon the copper surface 32 of an appropriate ornamental design 34 of acid resist. The resist coating is of conventional composition, well known to those skilled in the art, and comprising essentially a quick-drying ink capable of adhering to the metal surface and of resisting the action of the etching agent to be thereafter employed.

One manner of applying the resist coating 34 is by using a silk screen stencil. In such case, a black-on-White drawing of the design is rst made, after which a photographic negative is made from the drawing. A photographic positive'is then made from the negative and is employed to make the photographic silk screen stencil in a manner well known to those skilled in the art. 'Ille stencil is mounted in a frame which is then employed to print onto the metal surface in conventional manner.

The print is then dried (optionally force-dried by heatpurpose, this invention is not limited to the use of silkY screen printing. Thus, any conventional method of applyingvink or the like in appropriate design upon a metal surface can be employed instead.

After the resist coating v34 has been applied to the metal surface as indicated in Fig. 3, the plate is etched to remove the unprotected areas of the copper coating 32, so as to expose the underlying' resin plate 30, asindicated in Fig. 4.

This etching can be done, for example, by immersing the plate in a solution of ferric chloride, 40 Baum at approximately F. for about three minutes `in a paddle-type etcher. A longer time (about thirty minutes) is required in tank etching.

Instead of etching with a chemical solution, it is possible to etch electrolytically byV immersing the plate in a salt solution and connecting the metal layer as the anode of an electrolyticV circuit, whereby closing of the circuit causes the metal to dissolve off thev plate in a manner well known to those skilled in the art.

The etched plate is then rinsed olf and the resist coating 34 is removed by soaking for several minutes in mineral spirits or any other suitable solvent so as to expose the underlying copper surface 32 as indicated in Fig. 5.

In other words, after the etching and the subsequent removal of resist, the dark-colored resin plate 30 is visible at those areas which were not protected by the resist, while the copper surface is Visible at the remaining areas of the laminate.

The metal surface 32 is then polished and the entire surface is covered with a clear protective coating of lacquer or other suitable material, by spraying, dipping or any other appropriate manner.

VPrior to the application of the clear protective coating, it is possible to treat the surface of the laminate in Various ways so as to enhance its ornamental appearance. These supplemental operations may include silk screen printing, hand painting, electroplating, molding or post-forming of the borders or other parts of the resin plate, etc.

The plaque of Fig. l can be mounted directly upon a wall or can be enclosed within a suitableframe in an obvious manner.

Instead of being employed as separate pictures or the like, plaques like that of Fig. 1 can be set into table tops in the manner indicated in Fig. 20. Such table tops may be of wood, with vthe plaques adhesively secured thereto in a manner similar to that now employed with leather inserts.

Where the table top is of molded laminated synthetic resin (such as are now commonly employed on kitchen and dinette tables) the ornamental plaque may be molded flush with or covered over by the outermost transparent synthetic resin layer of the table top so as to form a more or less integral part thereof.

By employing larger size plaques, it is possible tov construct entire table tops thereof (in lieu of the inserts of Fig. 20); the frame of the table or other article ofV furniture being fastened directly to the undersidev of the synthetic resin base in any conventional manner.

In Figs. 6-12, there is indicated the manner of forming a three-color ornamented metal-on-resin laminate by selective printing and etching of two superimposed coatings of different metals, in which the metal of the outermost coating is higher in the electromotive series than the metal of the undercoating.

For purposes of illustration, there is shown, in Fig. 6, a synthetic resin plate 30 having a coating 32 of precious metal (as for example gold) and an outermost coating 36 of a base metal (as for example nickel).

A resist coating 38 is rst applied to the outermost base t metal?. coating.` 36 an appropriate design, as indicated in `the outermost base metal coating, but will not attack the underlying precious metal coating, so that the underlying base metal `coating is exposed at the unproteced` areas, in the manner indicated in Fig. 8.

Thereafter, the resist is. removed using mineral spirits, toluol` on any other` suitable solvent, to expose the remainder of the outermost base metal coating, as indicated in Fig. 9.

A second.A resist coating 40 is then applied, in appropriate design, so as to expose their areas, as illustrated in` Fig. 10. It is pointed out that, in the drawings, the thickness of the metal coatings is exaggerated, for clarity of illustration. In actual practice, the metal coatings are extremely thin (of the order of thousandths of an inch) so that, when the resist is imprinted onto the previouslyetched bi-metal surface, it is capable of lling the recesses Without diculty and without appreciable impairment of the sharpness of the printed design.

The laminate is then treated with an etching agent (as for example aqua regia) capable of dissolving out both the outermost base metal coating and the underlying precious metal coating at the unprotected areas, so as to expose the underlying resin plate 30, as indicated in Fig. ll.

Finally, the resist coating 40 is removed, as indicated in Fig. l2, to make both the resin base and the underlying precious metal coating visible in different areas, in contrast to the outermost base metal coating.

The three-color laminate is then polished an-d provided with a clear protective coating in a manner similar to that described hereinabove.

Also, as describedhereinabove, hand painting, silk screen printing, electro-plating, and other suitable ornamental operations can be performed on the surface of the embodiment of Figs. 6-12, prior to application of the clear protective coating.

In Figs. 13-19, there is indicated another method of forming a three-color ornamented metal-on-resin laminate by selective printing and etching of two superimposed coatings of different metals; the first etching operation dissolving out both metals in the unprotected areas, and the second etching operation dissolving out only the outermost metal layer in the unprotected areas.

Thus, in Fig. 13, the synthetic resin plate is provided with an undercoating 31 of aluminum and an outermost coating 33 of copper; an intervening coating 35 of zinc being rst applied to the aluminum undercoat, to make the copper adhere thereto.

A resist coating 37 is rst applied to the copper surface 33 in an appropriate design, as indicated in Fig. 14.

The laminate is then treated with nitric acid which removes the copper and zinc in the unprotected areas, after which the laminate is washed and further etched with ferrie chloride or sodium hydroxide to remove the aluminum and expose the synthetic resin base in the unprotected areas, as illustrated in Fig. l5.

The rst resist coating is then removed in the manner illustrated in Fig. 16.

A second resist coating is then applied in a new design; the resist filling the depressions formed during the rst etching and exposing other areas of the outermost copper coating, as indicated in Fig. 17.

The laminate is then treated with an etching agent, as for example nitric acid, which will dissolve the outermost copper coating and the intervening zinc coating in the unprotected areas, without attacking the aluminum undercoat, in the manner indicated in Fig. 18.

Instead of etching chemically at this stage, it is possible to etch electrolytieally, by immersing the laminate in a solution of an electrolyte and connecting the copper as the anode of an electric circuit, so as to dissolve off the copper andV the zinc without alfecting the aluminum, in a manner known to those skilled in the art.

It is also possible to remove the greatest part of the copper electrolytically, at this stage, and to remove the last traces of unprotected copper chemically. This latter procedure may be preferred over complete electrolytic etching because the latter is sometimes ineifective to remove the last traces of metal which become isolated from the area of electrical contact.

After the second etching operation has been completed, the second resist' coating is removed so as to make both the synthetic resintbase and theunderlying aluminum coatingtvisible in diiferent areas, in contrast to the outermost copper coating, in the manner illustrated in Fig. 19.

In Figs. 21-27 there is shown another embodiment of the present invention comprising a front panel for a portable radio or the like, in which the trade-mark or trade-name, tuning-dial numbers, switch insignia, etc., are formed, in contrastngly colored metal, on the outer side of a non-conductor synthetic resin plate, while an electrically-conducting printed circuit is formed on the inner side of the plate.

Thus, as indicated particularly in Fig. 21, the plate 42 (which may be of Bakelite or other appropriate non-conductor synthetic resin) can be provided with suitable shaft openings 44 as well as loud-speaker slits 46.

A manufacturers name or trade-mark 48, tuning-dial numbers S0 and switch insignia 52 can be formed on the outer face of the plate 42 by printing on an outer metallic coating 54 with a resist 56, etching away the unprotected areas of the metal coating, and thereafter dissolving off the resist, in a manner to be more fully described hereinbelow.

A printed circuit 58 of electrically conducting metal can be formed on the inner face of the plate 42, as indicated in the fragmentary View of Fig. 22, which shows the band-switch part of the circuit.

The printed circuit is formed by imprinting a suitable resist coating 60 of electrically conducting metal or the like; subsequently etching away the unprotected areas of the coating, and finally dissolving away the resist coating.

The various steps of forming the panel. of Fig. 2l are illustrated in Figs. 23-27.

Thus, Fig. 23 is a fragmentary cross-sectional view of the panel taken generally along the line 23--23 of Fig. 22 but before the shaft holes and loud speaker slits have been formed therein; the outer metallic coating 54 and the inner conducting metal coating 60 being shown as applied to the outside and inside faces of the synthetic resin plate 42.

In Fig. 24, the resist coatings 56 and 62 are shown as applied to the surfaces 54 and 60 respectively in appropriate designs.

Fig. 25 shows the appearance of the laminate after the unprotected portions of the coatings 54 and 60 have been etched away, employing ferric chloride or other suitable etching agent.

In Fig. 26, the resist coatings have been removed so as to expose the switch insignia 52 (as well as the trade-mark 48 and tuning-dial numbers 50) on the outside surface and to expose the printed circuit 58 on the inside surface of the resin plate 42.

Fig. 27 shows the appearance of the laminate after the shaft holes 44 (and also the loud-speaker slits 46) have been formed therein.

The metal surfaces are then polished and covered with a protective coating, except at those parts of the printed circuit 58 where electrical contact, wiping Contact or soldering is necessary.

The present invention may be embodied in other specific forms and, therefore, the foregoing embodiments are to be considered merely as illustrative and not restrictive, reference being made to the appended claims as indicating the scope of this invention.

`and desire to protect by Letters Patent the following:

1. A method of forming an ornamented surface which includes the steps of forming a laminate comprising at least two layers of diierent metals upon a nonmetal base; applying a coating of resist material, in appropriate design, to the outermost metal surface; treating the resistcoated laminate so as to remove the metal in the areas not covered by the resist; removing the resist coating; applying a second coating of resist material in a dierent design; treating the resist coated laminate so as to remove the metal in the areas not covered by the resist; and subsequently removing the second resist coating; one of the metal-removing operations being such that both metal layers are removed thereby, while the other metal-removing operation is such that only the metal of the outermost layer is removed thereby; whereby the nonmetal base and the under metal layer are visible in different areas in contrast to the outer metal coating.

2. A method according to claim 1 wherein only the Vouter metal coating is removed in the unprotected areas during the rst etching operation, and wherein both metal coatings are removed in the unprotected areas duringA the second etching operation.

3. A method according to claim l wherein both metal layers are removed in the unprotected areas during the rst etching operation, and wherein only the outer metal layer is removed in the unprotected areas during the second etching operation.

References Cited in the le of this patent UNITED STATES PATENTS 2,441,960 Eisler a May 25, 1948 

1. A METHOD OF FORMING AN ORNAMENTED SURFACE WHICH INCLUDES THE STEPS OF FORMING A LAMINATE COMPRISING AT LEAST TWO LAYERS OF DIFFERENT METALS UPON A NONMETAL BASE; APPLYING A COATING OF RESIST MATERIAL, IN APPROPRIATE DESIGN, TO THE OUTERMOST METAL SURFACE; TREATING THE RESISTCOATED LAMINATE SO AS TO REMOVE THE METAL IN THE AREAS NOT COVERED BY THE RESIST; REMOVING THE RESIST COATING; APPLYING A SECOND COATING OF RESIST MATERIAL IN A DIFFERENT DESIGN; TREATING THE RESIST COATED LAMINATE SO AS TO REMOVE THE METAL IN THE AREAS NOT COVERED BY THE RESIST; AND SUBSEQUENTLY REMOVING THE SECOND RESIST COATING; ONE OF THE METAL-REMOVING OPERATIONS BEING SUCH THAT BOTH METAL LAYERS ARE REMOVED THEREBY, WHILE THE OTHER METAL-REMOV- 